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Aims: To detect functional connectomes of akinetic‐rigid (AR) and tremor and compare their connection pattern. Methods: Resting‐state functional MRI data of 78 drug‐naïve PD patients were enrolled to construct connectomes of AR and tremor via connectome‐based predictive modeling (CPM). The connectomes were further validated with 17 drug‐naïve patients to verify their replication. Results: The connectomes related to AR and tremor were identified via CPM method and successfully validated in the independent set. Additional regional‐based CPM demonstrated neither AR nor tremor could be simplified to functional changes within a single brain region. Computational lesion version of CPM revealed that parietal lobe and limbic system were the most important regions among AR‐related connectome, and motor strip and cerebellum were the most important regions among tremor‐related connectome. Comparing two connectomes found that the patterns of connection between them were largely distinct, with only four overlapped connections identified. Conclusion: AR and tremor were found to be associated with functional changes in multiple brain regions. Distinct connection patterns of AR‐related and tremor‐related connectomes suggest different neural mechanisms underlying the two symptoms. [ABSTRACT FROM AUTHOR]

Objective: To determine whether white matter hyperintensity (WMH) volumes in specific regions are associated with Parkinson's disease (PD) compared to non‐PD controls, and to assess their impact on motor signs through cross‐sectional and longitudinal analyses. Methods: A total of 50 PD participants and 47 age‐ and gender‐matched controls were enrolled. All PD participants were followed up for at least 2 years. To detect regions of greater WMH in the PD, the WMH volume of each region was compared with the corresponding region in the control group. Linear regression and linear mixed effects models were respectively used for cross‐sectional and longitudinal analyses of the impact of increases in WMH volume on motor signs. Results: The PD group had greater WMH volume in the occipital region compared with the control group. Cross‐sectional analyses only detected a significant correlation between occipital WMH volume and motor function in PD. Occipital WMH volume positively correlated with the severity of tremor, and gait and posture impairments, in the PD group. During the follow‐up period, the participants' motor signs progressed and the WMH volumes remained stable, no longitudinal association was detected between them. The baseline occipital WMH volume cannot predict the progression of signs after adjustment for baseline disease duration and the presence of vascular risk factors. Interpretation: PD participants in this study were characterized by greater WMH at the occipital region, and greater occipital WMH volume had cross‐sectional associations with worse motor signs, while its longitudinal impact on motor signs progression was limited. [ABSTRACT FROM AUTHOR]

Background: Dysfunction of iron metabolism, especially in substantia nigra (SN), is widely acknowledged in Parkinson's disease (PD), but the genetic influence on iron deposition remains largely unknown. Thus, in this study, we aimed to investigate potential genetic impacts on iron deposition in PD. Methods: Seventy‐four subjects, including 38 patients with PD and 36 age‐matched normal controls, participated in this study. Imaging genetic association analysis was used to identify the specific influence of single nucleotide polymorphism (SNP) on iron‐related quantitative traits (QT). Genetic effects on iron deposition at the disease level, SNP level, and their interactive effect were highlighted. Results: Four strong SNP–QT associations were detected: rs602201‐susceptibility of bilateral SN, rs198440‐susceptibility of left SN, and rs7895403‐susceptibility of left caudate head. Detailed analyses showed that: (1) significant iron deposition was exclusively found in bilateral SN in PD; (2) altered polymorphisms of the A allele/A− genotype of rs602201 and G allele/G− genotype of rs198440 and rs7895403 were more frequently observed in PD; (3) for rs602201, among all subjects, A− genotype carriers showed significantly increased iron content than TT genotype in bilateral SN; for rs198440 and rs7895403, G− carriers showed increased iron content than AA genotype in left SN and left caudate head, respectively; and (4) rs602201 exhibited significant SNP‐by‐disease interaction in bilateral SN. Conclusions: This study shows that rs602201 and rs198440 have a stimulative impact on nigral iron deposition in PD, which provides improved understanding of iron‐related pathogenesis in PD, and specifically, that vulnerability to iron deposition in SN is genetic‐based. [ABSTRACT FROM AUTHOR]

Background: Parkinson's disease (PD) is highly heterogeneous reflected by different affected side of body and type of motor symptom. We aim to explore clinical characteristics and underlying brain structure alterations in PD with different predominant sides and motor types. Methods: We recruited 161 PD patients and 50 healthy controls (HC). Patients were classified into four subtypes according to their predominant side and motor type: left akinetic/rigid‐dominant (LAR), left tremor‐dominant (LTD), right akinetic/rigid‐dominant (RAR), and right tremor‐dominant (RTD). All participants assessed motor and cognitive performances, then underwent T1‐weighted and diffusion tensor imaging scanning. A general linear model was used to compare neuroimaging parameters among five groups. Results: Among four PD subtypes, patients of LAR subtype experienced the worst motor impairment, and only this subtype showed worse cognitive performance compared with HC. Compared with HC and other subtypes, LAR subtype showed a significant reduction in cortical thickness of the right caudal‐anterior‐cingulate gyrus and fractional anisotropy of the right cingulum bundle. Conclusions: We demonstrated that LAR subtype had the worst clinical performance, which the severer damage in the right cingulate region might be the underlying mechanism. This study underscores the importance of classifying PD subtypes based on both the side and type of motor symptom for clinical intervention and research to optimize behavioral outcomes in the future. [ABSTRACT FROM AUTHOR]

Identifying a whole‐brain connectome‐based predictive model in drug‐naïve patients with Parkinson's disease and verifying its predictions on drug‐managed patients would be useful in determining the intrinsic functional underpinnings of motor impairment and establishing general brain–behavior associations. In this study, we constructed a predictive model from the resting‐state functional data of 47 drug‐naïve patients by using a connectome‐based approach. This model was subsequently validated in 115 drug‐managed patients. The severity of motor impairment was assessed by calculating Unified Parkinson's Disease Rating Scale Part III scores. The predictive performance of model was evaluated using the correlation coefficient (rtrue) between predicted and observed scores. As a result, a connectome‐based model for predicting individual motor impairment in drug‐naïve patients was identified with significant performance (rtrue =.845, p <.001, ppermu =.002). Two patterns of connection were identified according to correlations between connection strength and the severity of motor impairment. The negative motor‐impairment‐related network contained more within‐network connections in the motor, visual‐related, and default mode networks, whereas the positive motor‐impairment‐related network was constructed mostly with between‐network connections coupling the motor‐visual, motor‐limbic, and motor‐basal ganglia networks. Finally, this predictive model constructed around drug‐naïve patients was confirmed with significant predictive efficacy on drug‐managed patients (r =.209, p =.025), suggesting a generalizability in Parkinson's disease patients under long‐term drug influence. In conclusion, this study identified a whole‐brain connectome‐based model that could predict the severity of motor impairment in Parkinson's patients and furthers our understanding of the functional underpinnings of the disease. [ABSTRACT FROM AUTHOR]

Background: Excessive iron accumulation is one of the main pathogeneses of Parkinson's disease (PD). Ceruloplasmin plays an important role in keeping the iron homoeostasis.Purpose: To explore the association between serum ceruloplasmin depletion and subcortical iron distribution in PD.Study Type: Prospective.Population: One hundred and twenty-one normal controls, 34 PD patients with low serum ceruloplasmin (PD-LC), and 28 patients with normal serum ceruloplasmin (PD-NC).Sequence: Enhanced susceptibility-weighted angiography (ESWAN) on a 3 T scanner.Assessment: Quantitative susceptibility mapping was employed to quantify the regional iron content by using a semi-automatic method. Serum ceruloplasmin concentration was measured from peripheral blood sample. Clinical assessments were conducted by a neurologist.Statistical Tests: General linear model was used to compare the intergroup difference of region iron distribution among groups, and the statistics was adjusted by Bonferroni method (P < 0.01). Partial correlation analysis was used to detect the association between regional iron distribution and serum ceruloplasmin concentration (P < 0.05).Results: Compared with normal controls, significant iron accumulation in substantia nigra, putamen, and red nucleus was observed in PD-LC, while the only region showing significant iron accumulation was SN in PD-NC. Between PD-NC and PD-LC, the iron accumulation in putamen remained significantly different, which had a negative correlation with serum ceruloplasmin in whole PD patients (r = -0.338, P = 0.008).Data Conclusion: Nigral iron accumulation characterizes PD patients without significant association with serum ceruloplasmin. Differentially, when PD patients appear with reduced serum ceruloplasmin, more widespread iron accumulation would be expected with additionally involving putamen and red nucleus. All these findings provide insightful evidence for the abnormal iron metabolism behind the ceruloplasmin depletion in PD. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: 2. [ABSTRACT FROM AUTHOR]

Undesired photoelectronic dormancy through active species decay is adverse to photoactivity enhancement. An insufficient extrinsic driving force leads to ultrafast deep charge trapping and photoactive species depopulation in carbon nitride (g‐C3N4). Excitation of shallow trapping in g‐C3N4 with long‐lived excited states opens up the possibility of pursuing high‐efficiency photocatalysis. Herein, a near‐field‐assisted model is constructed consisting of an In2O3‐cube/g‐C3N4 heterojunction associated with ultrafast photodynamic coupling. This In2O3‐cube‐induced near‐field assistance system provides catalytic "hot areas", efficiently enhances the lifetimes of excited states and shallow trapping in g‐C3N4 and this favors an increased active species density. Optical simulations combined with time‐resolved transient absorption spectroscopy shows there is a built‐in charge transfer and the active species lifetimes are longer in the In2O3‐cube/g‐C3N4 hybrid. Besides these properties, the estimated overpotential and interfacial kinetics of the In2O3‐cube/g‐C3N4 hybrid co‐promotes the liquid phase reaction and also helps in boosting the photocatalytic performance. The photocatalytic results exhibit a tremendous improvement (34‐fold) for visible‐light‐driven hydrogen production. Near‐field‐assisted long‐lived active species and the influences of trap states is a novel finding for enhancing (g‐C3N4)‐based photocatalytic performance. [ABSTRACT FROM AUTHOR]

The overall water splitting efficiency is mainly restricted by the slow kinetics of oxygen evolution. Therefore, it is essential to develop active oxygen evolution catalysts. In this context, we designed and synthesized a tungsten oxide catalyst with oxygen vacancies for photocatalytic oxygen evolution, which exhibited a higher oxygen evolution rate of 683 μmol h−1 g−1 than that of pure WO3 (159 μmol h−1 g−1). Subsequent studies through transient absorption spectroscopy found that the oxygen vacancies can produce electron trapping states to inhibit the direct recombination of photogenerated carriers. Additionally, a Pt cocatalyst can promote electron trap states to participate in the reaction to improve the photocatalytic performance further. This work uses femtosecond transient absorption spectroscopy to explain the photocatalytic oxygen evolution mechanism of inorganic materials and provides new insights into the design of high‐efficiency water‐splitting catalysts. [ABSTRACT FROM AUTHOR]

Background: Motor disturbances in Parkinson's disease (PD) mainly result from the degeneration of classic motor pathways. Given that the specific limbic pathway participates in movements, it is reasonable to consider that limbic pathway have the pathologic potential of motor disturbance in PD. Purpose To explore the white matter changes of limbic and motor pathways and their relations in PD patients. Study Type: Prospective. Population: 39 PD patients and 55 normal controls. Sequence Sagittal 3D T1‐weighted fast spoiled gradient recalled sequence, diffusion‐weighted spin echo‐echo planar imaging sequence on a 3T scanner. Assessment Probabilistic tractography was used to reconstruct the motor pathways (nigrostriatal−nigropallidal and basal ganglia−motor cortex pathways) and limbic pathway (amygdala−accumbens−pallidum pathway). White matter alterations of these pathways were evaluated by fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), radial diffusivity (RD), neurite density (NDI), and orientation dispersion (ODI). Clinical assessment was conducted by a neurologist. Statistical Tests: Group comparisons were performed using unpaired t‐tests. Pearson or Spearman correlation was used to explore the relationships between variables. Results: Compared with normal controls, PD patients showed decreased ODI as well as increased MD and AD in the bilateral nigrostriatal−nigropallidal pathway (P < 0.05), decreased FA in left basal ganglia−motor cortex pathway (P < 0.05), and decreased ODI in left limbic pathway (P < 0.05). MD and AD in the left nigrostriatal−nigropallidal pathway was negatively correlated with FA in left basal ganglia−motor cortex pathway (r = −0.597, P < 0.05 and r = −0.433, P < 0.05, respectively). MD in the left nigrostriatal−nigropallidal pathway was significantly correlated with ODI in the left limbic pathway (r = −0.404, P < 0.05). ODI was associated with AD within each hemisphere of the nigrostriatal−nigropallidal pathway (r = −0.591, P < 0.05 for left; r = −0.589, P < 0.05 for right). Data Conclusion: The relationship between the degenerated motor pathways and aberrant limbic pathway suggest the existence of neuronal modulation between motor and limbic pathways, providing novel evidence of the neuromechanism for motor disruption in PD patients. Level of Evidence: 2 Technical Efficacy Stage: 1 J. MAGN. RESON. IMAGING 2020;52:1799–1808. [ABSTRACT FROM AUTHOR]

Laminectomy has been widely considered one of the most common treatments for lumbar disorders. Epidural fibrosis (EF) is a common complication after laminectomy, causing recurrent postoperative pain. Schisandrin B (Sch.B), the active ingredient extracted from Schisandra chinensis Fructus, has been found to have potent antiproliferative and antifibrotic effects on several cells. This study aimed to investigate the effects of Sch.B on the prevention of postlaminectomy EF formation. In vitro, we studied the effects of Sch.B on transforming growth factor beta 1 (TGF-β1)-induced proliferation and extracellular matrix (ECM) production of primary fibroblasts, as well as its underlying mechanism. We found that Sch.B not only inhibited the proliferation of fibroblasts but also reduced ECM production, including that of connective tissue growth factor, fibronectin, and type I collagen, in a dose-dependent manner. Mechanistically, we found that Sch.B suppressed TGF-β1-stimulated activation of the Smad2/3 and mitogen-activated protein kinase pathways. Moreover, the in vivo study demonstrated that Sch.B treatment attenuated the progression of EF in a postlaminectomy rat model via reducing the cell number and ECM production of scar tissue. Taken together, these data suggested that Sch.B possesses great potential value as a preventative agent for EF. [ABSTRACT FROM AUTHOR]

Herein, we report the high activity of CuO-SnO2 catalysts for the catalytic oxidation of CO. In particular, SnCu30 shows the highest activity and a high water resistance. If we compare the XRD, X-ray absorption fine structure, and H2 temperature-programmed reduction results of SnCu30 before and after HNO3 treatment, we find the existence of three kinds of Cu species in the catalyst, that is, highly dispersed CuO, bulk CuO, and Cu incorporated in the SnO2 lattice. The highly dispersed CuO and the surface lattice oxygen species are the active sites for the catalytic oxidation of CO. We used X-ray photoelectron spectroscopy and in situ diffuse reflectance infrared Fourier transform spectroscopy to confirm the existence of Cu+ species on the surface of the CuO-SnO2 catalysts, which can provide the adsorption sites for CO. Our results show that the reaction pathways of the catalytic oxidation of CO over the CuO-SnO2 catalysts follow the Mars-van Krevelen model. [ABSTRACT FROM AUTHOR]